At the march were protesters from the Campaign for Nuclear Disarmament, environmental groups, church organisations, the ruling Scottish National Party, Scottish Socialist Party, and Scottish Green Party members. The movement was united under the banner of the Scrap Trident campaign. The protest is part of a weekend of anti-nuclear events in Scotland, with workshops planned in George Square Sunday and a blockade of Faslane Naval Base, where the Trident missile system is located, Monday.

Trident enables the delivery of up to 200 nuclear tipped warheads to targets from submarines. The British government has said that replacing the Trident warheads could cost British taxpayers a little over £20 billion ($31 billion, €23 billion), but Greenpeace estimates that the long term costs could soar as high as £130 billion ($200 billion, €152 billion) over the lifetime of the warheads. Scrap Trident wants the funds for the replacement of the nuclear arsenal to be instead used on public services.

The government originally estimated the cost of replacing Britain’s four Trident submarines would set back taxpayers £25bn.

But manufacturing costs have now been revised up to at least £31bn, according to the Prime Minister’s defence review.

And the government has set aside a further £10bn as a “contingency” fund in case it blows the original budget.

“The revised cost and schedule reflect the greater understanding we now have about the detailed design of the submarines and their manufacture,” the defence review document states.

The nuclear weapons spending boom comes just two days before Chancellor George Osborne is expected to announce 30 per cent cuts to some public services.

The estimate does not even take into account the cost of servicing the submarines throughout their lifetime.

Tory MP Crispin Blunt, chair of the Commons foreign affairs committee, said last month that the total cost of servicing Trident would be £142bn.

Campaign for Nuclear Disarmament general secretary Kate Hudson said: “This is outrageous — the government has completely lost control of the budget.

“With the cost of new submarines rising by 60 per cent to £41bn — and in addition to the £142bn in-service costs reported by Crispin Blunt MP last month — Trident replacement could now rise to a staggering £183bn.”

“The simplest question to ask ourselves and the most difficult to answer is, in those circumstances, who will those Trident missiles be aimed at,” he said.

The Prime Minister also announced billions will be spent on two new 5,000-strong army “strike brigades,” a 10-year extension to the operational lifespan of the RAF’s Typhoon jets and new equipment for the SAS.